Fracture testing of welded single edge notch tensile specimens

The fracture behavior of welded single edge notched tension specimens was examined using constraints and loading conditions which approximated those of a flawed ship structural panel. The specimens were notched and fatigue pre-cracked in the microstructural region associated with a brittle coarse grained heat affected zone and dynamically fractured at the minimum design temperature. In all cases, the fracture event was preceded by some degree of plasticity. With the aid of validated finite element method companion models, a crack mouth to crack tip opening displacement transfer function was generated allowing the fracture toughness at failure to be determined.

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► Fracture toughness tests at intermediate rates result in cleavage fracture along a weld’s heat affected zone.
► Validated finite element analyses generated a transfer function between the crack mouth and crack tip opening displacements.
► Despite failing in a brittle manner, the estimated CTOD exceeds the minimum fracture toughness.
► A parametric study suggests that the presence of a weld shields a crack located in the heat affected zone.